Search PubMed⌕ Search

Biomedical subjects

A N Shenderov

Publications and source records attributed to A N Shenderov.

8 recordsLinked to original sources
PubMed1988

[Comparative restriction analysis of chromosomal DNA of strains of Photobacterium leiognathi].

Chromosomal DNA in 5 hereditary variants occurring in Photobacterium leiognathi population was subjected to restriction analysis. The variants differed in the levels and regulation of luminescence and colony morphology. Agarose electrophoresis of DNA fragments isolated after exposure to Hind II, Bam HI, Bgl I and Pst I restriction endonucleases revealed respectively 38, 28, 35 and 29 fragments equally distributed by their molecular weights. Electrophoregrams of the 5 strains were absolutely identical. After exposure of DNA of all the strains to PVu II, Xho II, Sal GI and Eco RI restriction endonucleases there were detected no fragments. The pleoiotropic genetic variation in these strains was not associated with large deletions or amplification of chromosomal DNA regions.

Chromosomes, Bacterial↗
PubMed1988

[Cloning and insertion mutagenesis of DNA fragment coding for the luminescent system of Photobacterium leiognathi].

Fragments of DNA, obtained from the luminescent bacterium Photobacterium leiognathi and inserted into the plasmid pBR322, were found to code for the luminescence expressed in E. coli cells. The genetic functions necessary for light production in E. coli are localized on a DNA fragment of about 7 kbp. The insertion mutagenesis was used to define the luminescence functions encoded by the hybrid plasmid.

Cloning, Molecular↗
PubMed1983

[Pathway of synthesis of the aldehyde factor - a basic substrate of luciferase].

The stimulation of luminescence and cell aldehyde factor during the growth of one-aldehyde-dependent mutant in the condition medium by other aldehyde-dependent mutants was studied. It was shown that the aldehyde factor is synthesized in five successive steps, thus suggesting the participation of five enzymes in aldehyde factor synthesis. The metabolite accumulation in the condition medium increases both the level of the aldehyde factor and that of luciferase. It is assumed that some precursors of the aldehyde factor are involved in the regulation of the luminescence development.

Aldehydes↗
PubMed1979

[Genetic studies of Photobacterium mandapamensis. II. The classification of mutants with an altered luminescence intensity according to their sensitivity to exogenous aldehyde].

The collection of 157 dark and dim Photobacterium mandapamensis strains was divided into four groups using the addition of 0.2 ml of 0.15% myristis aldehyde to cell suspension. The luminescence did not change in the presence of the aldehyde in 76 mutants, it decreased in 30 mutants, it was 2--8-fold increased in 35 mutants, and it was increased more than 10-fold in 16 mutant strains. 19 strains of those having luminescence in the presence of the aldehyde have mutations in genes controlling the biosynthesis of the aldehyde factor. Among them mutants are chosen which can be used as indicators for the aldehyde presence in the medium.

Aldehydes↗
PubMed1978

[Isolation of bacterial luminescence reaction inhibitor from Photobacterium sp. cells].

The factor having a strong inhibitory effect on bacterial luminescence was isolated from the luminous bacteria species Photobacterium sp. The inhibitor purified by gel filtration on the biogel and by DEAE chromatography was homogenous (single bound during electrophoresis in polyacrylamide gel), it reacted with coomassie brilliant blue and gave a positive Lowry reaction on protein. Molecular weight was about 30,000 as determined by SDS-polyacrylamide gel electrophoresis. The absorption spectrum was characterised by the maximum at 209 nm and unexpressed maximum in the region of 260 nm. It was shown that the inhibitor had an efficient inhibitory effect on both partially- and highly purified luciferase preparations from different species of luminous bacteria, but it produced no effect on the activity of specific NADH: FMN-oxidoreductase.

Bacterial Proteins↗
PubMedDate not supplied

[Effect of cAMP on the growth and development of luminescence in Photobacterium belozerskii].

The effect of cAMP on the parameters characterizing the development of luminescence in Photobacterium belozerskii is discussed. An addition of cAMP to the culture medium shortened the latent time of luminescence development by 3--6 hours. The intensity of bacterial luminescence increased with a varying rate. During luminescence enhancement the rate of luciferase synthesis increased by a factor of 10 to 10(3). The rate of luciferase synthesis and the maxiumum level of bacterial luminescence when cultivated in the glycerol medium containing arginine and proline increased under the influence of cAMP by 100 and 40 times, respectively. After an addition to cAMP into the glucose medium these parameters of luminescence development increased only when the medium contained arginine. After an addition of cAMP into the glycerol medium the rate of bacterial growth increased two-fold. Possible mechanisms regulating luminescence development and cAMP involvement in these processes are discussed.

Cyclic AMP↗
PubMedDate not supplied

[Effect of amino acids on the luminescent system induction in Photobacterium belozerskii].

Variations in the intensity of luminescence of Photobacterium belozerskii grown on different media were studied. In the course of growth the luminescence intensity changed by 2 to 4 orders of magnitude, depending on the nutrient medium used. Exogenous myristic aldehyde added to the bacterial suspension at the time of luminescence measurement decreased the intensity to a degree, which was essentially independent from the initial level. The onset of an increase in the luminescence intensity depended on the nutrient medium. An addition of arginine, proline or asparagine to the medium reduced the latent period and simultaneously increased the luminescent intensity by 30, 10 and 5-10 times, respectively. Arginine and proline added to the minimal medium at the time of an increase in the luminescence of P. belozerskii enhanced the rate of biosynthesis of the luminescent system enzymes by 32 and 10 times, respectively. In response to a combined action of these amino acis, the rate of luciferase biosynthesis grew by 630 times. Possible mechanisms and factors responsible for the above changes are discussed.

Amino Acids↗